Field of the Invention
The present invention relates to a technique of detecting a user's operation with reference to a movement region extracted from an image.
Description of the Related Art
A technique of extracting a region including an image of a specific object, such as a user's hand, from an image obtained by a visible light camera, an infrared camera, or a range image sensor and recognizing a UI (User Interface) operation by a gesture in accordance with a movement and a position of the object has widely used. A technique of recognizing an operation by measurement of a three-dimensional position of an object instead of detection of a touch on a touch panel has been used for tabletop interfaces which display images and UIs on table surfaces and operate the images and UIs by touching.
Japanese Patent Laid-Open No. 2013-257686 discloses a system which detects a user's hand in accordance with a difference between frames in a video image captured by a camera and which recognizes a gesture operation performed on a projected UI component.
To detect a touch of an object on a touch target surface in accordance with measurement of a three-dimensional position, a distance between the touch target surface and the object may be measured and a state in which the distance is smaller than a predetermined threshold value may be determined as a state in which the touch target surface is touched.